Can you check my homework?

Which of these are compound sentences?
1. My cat licked my face when I came home from school. NO (simple)

2. I am worried, because my cat is missing.
No (complex)

3. Sarah did her homework, and then she went to the party. YES

4. Kevin went to the movies and had fun. NO
(simple)

5. My cousin is coming over this weekend, so I know we’ll have fun.YES

6. The audience was completely silent at first, but then they cheered loudly.YES

7. We bought cereal, milk, and fruit at the grocery store. NO (simple)

All are correct except that #1 isn't a simple sentence (but it isn't compound either).